Electricity distribution is the penultimate stage in the delivery (before retail) of electricity to end users. It is generally considered to include medium-voltage (typically less than 50 kV) power lines, electrical substations and pole-mounted transformers, low-voltage (typically less than 1000 V).
In transformer arrangement used for electrical power distribution a reactor coil is sometimes employed. A reactor coil is an electrical device used for generating reactive power. Reactors are used in many different environments. One application for a reactor is as a grounding reactor, used in alternating-current power transmission systems. It can then be designed and used to limit the current flowing to ground at the location of a fault almost to zero by setting up a reactive current to ground that balances the capacitive current to ground flowing from the lines. Such an arrangement is also known as a Petersen coil.
Hence, a transformer supplemented by a reactor connected to a neutral node of the primary side of the transformer is typically used in a transformer arrangement in the distribution network of an electrical power transmission system.
The combination of a transformer and a reactor is typically used at the primary side of an electricity distribution network. The transformer arrangement is heavy and there is a desire to make such transformer arrangements with lower weight without reducing performance. Also because the transformer arrangement is heavy and made of fairly costly material there is a desire to reduce the amount of material required to manufacture such a transformer arrangement.
Therefore there exists a need for a reactor core that is easy to manufacture and which requires less material than a conventional reactor core, thereby making it weigh less.